Gameplay elements that were ahead of their time?

[Euphoria14]

I have a bunch bottled up in this strange head of mine but I am curious to see who here shares my thoughts.

My first example is the Xenogears battle system, I thought it was one of the most incredible systems I have played when it first came out and felt it was ahead of it's time.

 

Any games and/or gameplay elements past or present that you feel are ahead of their time?